Influenza Vaccine-Induced CNS Demyelination in a 50-Year-Old Male

PATIENT Male, 50. FINAL DIAGNOSIS Acute post-vaccination CNS demyelinating disorder. SYMPTOMS Blurred vision • hemiparesis • hemiplegia • hypertonia • itching • paresthesia. MEDICATION -. CLINICAL PROCEDURE MRI. SPECIALTY Neurology. OBJECTIVE Rare disease. BACKGROUND There are several categories of primary inflammatory demyelinating disorders, which comprise clinically similar neurologic sequelae. Of interest, clinically isolated syndrome (CIS) and acute disseminated encephalomyelitis (ADEM) are 2 demyelinating conditions of the central nervous system (CNS), whose clinical similarity pose a significant challenge to definitive diagnosis. Yet, both remain important clinical considerations in patients with neurologic signs and symptoms in the context of recent vaccination. CASE REPORT We report a case of a 50-year-old Caucasian male with a course of progressive, focal, neurologic deficits within 24 h after receiving the influenza vaccine. Subsequent work-up revealed the possibility of an acute central nervous system (CNS) demyelinating episode secondary to the influenza vaccine, best described as either CIS or ADEM. CONCLUSIONS Case reports of CNS demyelination following vaccinations have been previously noted, most often occurring in the context of recent influenza vaccination. This report serves to document a case of CNS demyelination occurring 24 h after influenza vaccination in a middle-aged patient, and will describe some salient features regarding the differential diagnosis of CIS and ADEM, as well as their potential management.